Notably, amongst the significantly altered proteins in the WT/PFF ExE-EVs were the dihydropteridine reductase (QDPR), ATP synthase subunit alpha 1 (ATP5A1), Phosphoglycerate kinase 1 (PGK1), Solute carrier family 2 (SLC2A1), and the mitochondrial proteins Protein deglycase DJ-1 (DJ-1), Complement component 1 Q (C1QB1) and NADH-ubiquinone oxidoreductase (NDUFS1) (highlighted in Supplementary Table 4, WT-PFF vs WT-PBS), which are also differentially expressed in PD patient-derived exosomes [14], [66-68] and are related to metabolic, synaptic and mitochondrial functions. The gene discussed is PGK1; the disease is Parkinson disease.